Technical Field
The present invention relates to an input operation detection device, a projection apparatus, an interactive whiteboard, a digital signage, and a projection system. Particularly, the invention relates to an input operation detection device adapted to detect an input operation input by a user, a projection apparatus including the input operation detection device, an interactive whiteboard including the same, a digital signage including the same, and a projection system including the projection apparatus.
Description of Related Art
Interactive projection apparatuses have commercially been available. This kind of projection apparatuses has functions to allow its user to input letters and drawings on an image projected on a screen, to enlarge and reduce the size of the projected image, to turn pages, or the like.
In these functions, user's fingers, or a pen or a stick held by the user can be used as the inputting means to touch the screen, and the projection apparatus detects the position and movement of the inputting means and sends the detection results to, for instance, a computer.
That is, apparatuses having the above interactive functions include an input operation detection device to detect input operations input by the user.
For instance, Patent Literature 1 (Japanese Laid-Open patent application No. 2013-61552) discloses a projection apparatus including projecting means to project a projection image on a projection surface, imaging means to capture an image of an imaging area including the projection surface by a plurality of image sensors, distance acquisition means to acquire distance data representing a distance to an imaging target present in the imaging area based on the images obtained by the plurality of the image sensors, input part detection means to define the imaging target present within an predetermined range from the projection surface based on the acquired distance data and to detect the imaging target as an input part, and analyzing means to analyze input operation input to the projected image in accordance with the positions and/or movements of the input part on the projected image.